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How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...ions:
Individual insert/update operations in a retry loop; or
Locking the table and doing batch merge
Individual row retry loop
Using individual row upserts in a retry loop is the reasonable option if you want many connections concurrently trying to perform inserts.
The PostgreSQL documentation co...
How to reorder data.table columns (without copying)
I'd like to reorder columns in my data.table x , given a character vector of column names, neworder :
2 Answers
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How to align center the text in html table row?
I am using an HTML <table> and I want to align the text of <td> to the center in each cell.
7 Answers
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SQL Server loop - how do I loop through a set of records
...EGIN
SET @MyCursor = CURSOR FOR
select top 1000 YourField from dbo.table
where StatusID = 7
OPEN @MyCursor
FETCH NEXT FROM @MyCursor
INTO @MyField
WHILE @@FETCH_STATUS = 0
BEGIN
/*
YOUR ALGORITHM GOES HERE
*/
FETCH NEXT FROM...
Center image in table td in CSS
I've been trying to align an image to the center of the table td. It worked with setting margin-left to a specific value but it also increased the size of td too and that isn't exactly what I wanted
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Want to find records with no associated records in Rails
...
Just imagine you have 10000000 records in friends table. What about performance in that case?
– goodniceweb
Dec 20 '16 at 14:51
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How to join (merge) data frames (inner, outer, left, right)
...f performance is a major issue for you, you should also look into the data.table package - that's a whole new set of join syntax, but it's radically faster than anything we're talking about here.
– Matt Parker
Feb 12 '13 at 16:22
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When is SQLiteOpenHelper onCreate() / onUpgrade() run?
I have created my tables in my SQLiteOpenHelper onCreate() but receive
15 Answers
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EF Code First “Invalid column name 'Discriminator'” but no inheritance
I have a table in my database called SEntries (see below the CREATE TABLE statement). It has a primary key, a couple of foreign keys and nothing special about it. I have many tables in my database similar to that one, but for some reason, this table ended up with a "Discriminator" column on the EF P...
How to disable scrolling in UITableView table when the content fits on the screen
I have a few (grouped style) tables in my iphone app (only on part of the screen and added with Interface Builder though, not subclassed from UITableViewController ) that 80% of the time are small and will fit on the screen. When the table fits on the screen, I'd like to disable scrolling, to ma...